Fabric conveyor system

ABSTRACT

A fabric conveyor system for a textile web includes a plurality of guiding rollers pressing against one side of the web, a toothed driven belt pressed against the opposite side the web, and a plurality of pressure pads supporting a toothed side of the driven belt turned away from the opposite side of the web and formed with respective flank portions each providing an unsupported run for a maximum of one tooth.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a national phase of PCT/DE/91/00150 filed 22 Feb.1991 and based, in turn, upon German national application G 90 02 430.3filed 2 Mar. 1990.

FIELD OF THE INVENTION

Our present invention relates to a fabric conveyor system, particularlyfor automatic cutting and sewing installations for textile webs or thelike, whereby a textile web or individual pieces of material areconveyed, preferably at their edges, by continuous conveyors such asdriven belts towards work stations such as stations for folding, hemmingselvedge consolidation or the like, and whereby the textile web travelsbetween endless belts and a stationary rail, or stationary freelyrotatable rollers, and whereby means are provided for pressing thetextile web against the stationary rail, or rollers and the belt lyingwith its flat side against the textile web is supported on itsrespective opposite side by a plurality of elastic pressure pads.

BACKGROUND OF THE INVENTION

A fabric conveyor system of the above-described kind is known fromDE-A-38 44 581.

Such fabric conveyor systems are frequently used in automatic textilemachines of all kinds. In such systems it is most important to guide thetextile goods precisely to and between the work stations, in order toavoid irregularities. These irregularities can occur due to the slippageof the textile goods between the guides, but also due to the slippage ofthe smooth belt from its drive disk. When textile goods are referred tohere, generally we include in the definition any kind of flat goods madeof any material such as textile, plastic, cardboard, etc.

Special difficulties are encountered in guiding textile webs when thethickness of these webs varies. The slippage of the drive belt from itsdrive disk results in uneven belt speeds, which in turn produceirregularities in the goods at the work station. When the belt portionbetween the guide rollers sags, variations in the contact pressure onthe textile web occur over lengths of several meters.

From DE-A-38 44 581 a fabric conveyor system is known in which a smooth,flat belt is used as a continuous conveyor.

In this system, it is possible that slippage can occur between the guideor driving rollers and the belt, which can lead to irregularities in theguidance of the material.

Furthermore, this construction requires a pressure means, which pressesthe smooth face of the conveyor belt against the workpiece. For thispurpose in a boxlike hollow profile a pressure means in the form of aninflatable pressure hose is provided, which can act upon apressure-transmitting member consisting for instance of elementssubdivided in the longitudinal direction. This element subdivided inlongitudinal direction can be formed by a band element having individualsegments connected to each other by elastic webs. As already describedabove, this arrangement does not insure a slippage-free entrainmentbetween the guide or driving rollers and the endless belt of thecontinuous conveyor.

In addition considerable manufacturing and structural expenses arerelated to the arrangement of the pressure-medium-actuatable hose,including the pressure member actuated by the hose. Also the adjustmentto the variable thickness of the running textile web or the like may notbe satisfactory. In earlier systems it has been proposed to provideseveral pressure hoses as pressure elements which can be differentlyactuated. However this allows only an insufficient degree of adjustmentof the individual segments of the pressure-transmitting element.

Hence it is essential for the individual elements of thepressure-transmitting member not to be in fact separate elements, but atleast elements connected to each other by elastic webs.

OBJECT OF THE INVENTION

It is the object of the present invention to provide a fabric conveyorsystem capable of guiding the goods precisely over longer stretches andwith variable thickness of the goods and to ensure the absence ofslippage to a large extent at a uniform contact pressure of the web ofmaterial.

SUMMARY OF THE INVENTION

This object is attained, in accordance with the invention, in a fabricconveyor system, particularly for automatic cutting and sewinginstallations in textile webs or the like, whereby the textile webs areguided, preferably at their edges by continuous conveyors such as drivenbelts toward work stations such as stations for the folding, hemming,selvage consolidating or the like. The textile web is guided betweenendless belts or between a stationary rail or an endless belt orstationary freely rotatable rollers or an endless belt, with means forpressing the textile web against the stationary rail, a belt or therollers are provided.

A belt lies with its flat side against the textile web and is supportedon its opposite side by a plurality of elastic pressure pads.

The belt is a toothed belt and the elastic pressure pads pressingagainst the tooth side of the belt are arranged in the longitudinaldirection of the belt next to each other so a maximum of one toothfacing the pressure pads remains without support on the surface of thepressure pads in each gap between pressure pads.

The pressure pads can be arranged not only over a part of the belt widthbut over the entire effective length of the belt.

Each pressure pad can have a slot arranged approximately in the middleof its longitudinal dimension and transverse to the longitudinaldirection, engaging a holding pin which limits the uppermost position ofthe pressure pad.

On both sides of the holding pin, compression springs are provided whichare guided in blind holes of the pressure pad and in blind holes of astationary bar parallel to the pressure pads on a side thereof facingaway form the belt. The pressure pads can have inclined approach edgesin the direction of oncoming teeth of the toothed belt.

BRIEF DESCRIPTION OF THE DRAWING

The above and other objects, features and advantages of the inventionwill become more readily apparent from the following description,reference being made to the accompanying highly diagrammatic drawing inwhich:

FIG. 1 is a lateral view of the fabric conveyor in partial section; and

FIG. 2 is a section along the line II--II in FIG. 1.

SPECIFIC DESCRIPTION

FIG. 1 shows is a lateral view of a fabric conveyor according to theinvention. A textile web 2 is guided at its edges by an endless toothedbelt 1 between the latter and upper guide rollers 10. The toothed belt 1travels in the direction of arrow 11. On the toothed side of toothedbelt 1 a plurality of elastic pressure pads 3 are arranged, which hitagainst each other with their ends in the longitudinal direction of thebelt and provide a supporting contact with the downwards pointing blunttooth surfaces of toothed belt 1.

The toothed belt 1 is guided over guide rollers (not shown) which aredesigned like toothed disks and of which at least one is driven. A belt10' is provided between the guide rollers 10 and the web 2.

The pressure pads 3 are provided over the entire effective belt length.The length of the individual pressure pads 3 is selected in relationwith the tooth distribution of toothed belt 1, so that a maximum of onetooth with its surface facing the pressure pad 3 remains without contactwith the surface of pressure pad 3 at any gap in the support provided bythe surfaces of the pressure pad. In this way, when a tooth leaves thesurface of the pressure pad, there is always a subsequent tooth whichcomes in touch with it.

Each pressure pad 3 is provided approximately in the middle with a slot5 which engages with a holding pin 4 when the pressure pad 3 has reachedits uppermost position. On both sides of holding pin 4, compressionsprings 6 are provided which are guided in blind holes 7, 8, provided onone side in the pressure pad and on the other side in a stationary bar9. The pressure pads 3 are provided with a sloped edge 12 on the sideapproached by the toothed belt in the direction of arrow 11, in order toprevent the locking of a tooth against pressure pad 3.

FIG. 2 shows a cross section along II--II in FIG. 1. The pin 4 and thebar 9 are stationary, fixed to the machine frame. In the sectionedpressure pad 3, one can recognize the slot 5 with the pin 4 engagingtherein. The toothed belt 1 rests upon the pressure pad 3. The textileweb 2 is guided by the upper guide rollers 10.

We claim:
 1. A fabric conveyor, comprising:a support surface againstwhich a web can be pressed at an edge of said web on one side thereof,and extending along a transport path for said web; an endless beltbearing with an outer surface against another side of said web oppositesaid one side and running along said transport path, said belt beingformed on an inner side thereof turned away from said other side of theweb with uniformly spaced apart teeth; a succession of pressure padsextending over substantially an entire effective length of the beltengaging said web along said transport path, said pressure pads havingdownstream flanks with respect to a direction of travel of the belt andthe web along said transport path; support means for individuallysupporting said pressure pads, said pads having portions adjacent saidflanks inclined toward said belt in said direction of travel andproviding an unsupported run of the belt and dimensioned such that nomore than one tooth of the teeth of the belt is located at therespective portion of each pressure pad; and spring means individuallybearing upon said pads and urging same against said teeth to supportsaid belt over said effective length for yieldable movement of said padsand said belts toward and away from said support surface.
 2. The fabricconveyor defined in claim 1 wherein each pressure pad is formed with arespective slot opening toward said support surface and having arespective downstream portion providing a respective unsupported run ofthe belt, said slots having widths in said direction dimensioned withrespect to the spacing of said teeth such that no more than one tooth ofthe teeth of the belt is located at the said portion of each slot, saidportions of said slots being inclined toward said belt in said directionof travel and each of the slots receiving a pin forming the respectivesupport means.
 3. The fabric conveyor defined in claim 2 wherein saidsupport surface is provided with an array of rollers extending alongsaid transport path.
 4. The fabric conveyor defined in claim 3, furthercomprising a roller belt interposed between said array of rollers andsaid endless belt.
 5. The fabric conveyor defined in claim 2 whereinsaid spring means includes a pair of springs received in blind bores ofeach pad, braced against a stationary bar disposed along a side of saidpads turned away from said belt, and flanking each slot.
 6. The fabricconveyor defined in claim 2 wherein each of said pins in each of saidslots is positioned to limit movement of the respective pad toward saidsupport surface.